1. Field of the Invention
The present invention relates to a data processing system with distributed data storage and more particularly to a data processing system with a network architecture of the so-called "INTRANET" type, serving a business or an organization.
2. Description of Related Art
It is generally acknowledged that one of the key factors in the good health of a business or a company is directly dependent on the information in its possession. The term "information" should be understood in its most general sense. It includes internal company information (sales prices of products, production schedules, etc.) or information from outside the company (various data on the competition, of a commercial or technical nature, etc.).
In the current state of the art, the processing of this information naturally involves the use of increasingly powerful and complex data processing systems. The rapid reduction in the costs of hardware, particularly mass storage units (hard disks, magnetic tape or cartridge units, optical disks) makes it possible to store more and more data, locally or at remote sites.
Increasingly, data processing systems are joined in networks. Among these must be mentioned the rapidly expanding global "INTERNET" network, which allows dialogue among millions of computers spread throughout the world, including simple microcomputers for home use.
Likewise, companies use specific local area networks called "INTRANETS," which link the various data processing resources at one or more of their sites to one another.
Because of this, companies are faced with the urgent need to control the increasing ow of incoming information, and particularly, to store it in "places" where it can be easily accessed, moved and managed in the most efficient way possible, and at the lowest cost.
These data must also be protected, in the broadest sense of this term. In general, the concept known by the French abbreviation "D.I.C." (for "Availability, Integrity, Confidentiality") applies.
In effect, it is necessary to ensure the integrity of the data, whether against system failures or against malicious actions. It is also necessary to take "reservation" measures, since certain data can be confidential, or at least be limited to access by authorized users. Lastly, they must be made as available as possible, which specifically involves the use of backup measures or a certain redundancy in their storage, in order to compensate for hardware deficiencies or software errors.
Finally, once the choice of a storage system has been made, it is necessary to ensure the perenniality of the system. Specifically, it must be possible to adapt to future technologies without substantial modifications of the system.